Lions love catnip.

They will roll around and lick and do all the things a house cat does when handed a toy filled with the psychedelic kitty-cat plant. Not all big cats are equally susceptible to the plant’s chemical powers, and within a single species some respond more than others, including house cats. I bet it’s a real bummer to learn your pet cat is immune to catnip, but that’s genetics for you.

What is the capital of Bulgaria? If you don’t know, just take a guess. Seriously, any answer will be fine. Even Bolgonia – I won’t know, just say something so we can move on.

Ok, now, what is the capital of Italy? Are you sure about that?

Now take a moment and think about your own thinking. How confident are you right now that your guesses are correct? Very confident? What about being wrong? Can you feel an intuition about your own wrongness? If so, can you also feel the strength of that intuition? Maybe you don’t feel like one of your answers is a guess at all (especially if you live near Bulgaria). Maybe you feel that way about both answers. If you feel that way, how confident are you that you aren’t guessing and that you know for sure you know what you know and that you know what you know is a fact?

The guess, as a concept, is the fruit fly of cognitive science. Research into what goes on in your head when you guess has opened many doors, launched many explorations into how the brain works. It’s a perfect, simple, easy to produce metacognition. If you want to learn more about thinking about thinking, make people guess.

It’s difficult to be certain of much in life.

Not only are you mostly uncertain of what will happen tomorrow, or next year, or in five years, but you often can’t be certain of the correct course of action, the best place for dinner, what kind of person you should be, or whether or not you should quit your job or move to a new city. At best, you are only truly certain of a handful of things at any given time, and aside from mathematical proofs – two apples plus two apples equals four apples (and even that, in some circles, can be debated) – you’ve become accustomed to living a life in a fog of maybes.

Most of what we now know about the world replaced something that we thought we knew about the world, but it turned out we had no idea what we were talking about. This is especially true in science, our best tool for getting to the truth. It’s a constantly churning sea of uncertainty. Maybe this, maybe that – but definitely not this, unless… Nothing raises a scientist’s brow more than a pocket of certainty because it’s usually a sign that someone is very wrong.

Why do you work where you work? I mean, specifically, why do you do whatever it is that you do for a living?

I’m pretty sure that you can answer this question. The average person, according to the Bureau of Labor Statistics, spends between 11 and 15 years of his or her life at work. On the high end, that’s about a fifth of your time on Earth as a person capable of enjoying pumpkin pie and movies about robots. That’s a lot of time spent doing something for reasons unknown, so I doubt you would lift your shoulders and offer up open palms of confusion when it comes to this question. I’m just not so sure that the answer you come up with will be correct.

Here’s a fun word to add to your vocabulary: nescience. I ran across it a few months back and kind of fell in love with it.

It’s related to the word prescience, which is a kind of knowing. Prescience is a state of mind, an awareness, that grants you knowledge of the future – about something that has yet to happen or is not yet in existence. It’s a strange idea isn’t it, that knowledge is a thing, a possession, that it stands alone and in proxy for something else out there in reality that has yet to actually…be? Then, the time comes, and the knowledge is no longer alone. Foreknowledge becomes knowledge and now corresponds to a real thing that is true. It is no longer pre-science but just science.

Every once in a while you will ask yourself, “I wonder if I should quit?”

Should you quit your job? Should you end your relationship? Should you abandon your degree? Should you shut down this project?

These are difficult questions to answer. If you are like me, every time you’ve heard one of those questions emerge in your mind, it lingered. It began to echo right as you woke up and just as pulled the covers over your shoulders. In the shower, waiting in line, in all your quiet moments – a question like that will appear behind your eyes, pulsating like a giant neon billboard until you can work out your decision.

When I was a boy, I spent my summers with my grandparents. They, like many Southerners, had a farm populated with animals to eat and animals to help. It was everywhere alive with edible plants – fields of corn and cucumbers and peas and butterbeans and peanuts, and throngs of mysterious life from stumps claimed by beds of ants to mushroom fairy rings, living things tending to business without our influence.

Remembering it now, I can see the symmetry of the rows, and the order of the barns, the arrangement of tools, the stockpiles of feed. I remember the care my grandmother took with tomatoes, nudging them along from the soil to the Ball jars she boiled, sealing up the red, seedy swirls under lids surrounded by brass-colored shrink bands. I remember my grandfather erecting dried and gutted gourds on polls so Martins would come and create families above us and we wouldn’t suffer as many mosquito bites when shelling peas under the giant pecan tree we all used for shade.